Fly Control Products

A UV or LED tube draws flies towards the unit, where they contact an electrified grid that kills them on contact. They run continuously, so they suit places flies keep arriving - kitchens, utility rooms, outbuildings - and work best in low ambient light, which makes them more effective indoors and at dusk than in bright daylight.

Match it to the situation rather than the fly. Sprays act on the flies present at the time. Traps and electric killers run continuously and suit anywhere flies keep coming back. Fly screens stop them entering at all, which is the only option that deals with the cause rather than the symptom. Most homes with a recurring problem need a screen plus one of the others.

Size and location tell you most of it. Large flies around windows and bins, one or two at a time, are house or blow flies coming in from outside. Dozens appearing in an upstairs room or loft in autumn are cluster flies overwintering, and they will keep emerging on warm days. Tiny flies hovering around fruit, bins or plugholes are fruit flies or drain flies, which breed indoors and need the breeding site cleaned rather than the adults sprayed.

Both. House flies and bluebottles feed at drains, decaying matter and animal waste, and they liquefy food before feeding, which transfers bacteria from their feet and gut - salmonella, E. coli and typhoid among them. That is why covering food, cleaning surfaces and removing the breeding source matters more than swatting the adults. Cluster flies are the exception: they do not bite or spread disease and are not a hygiene problem at all.

Traps, fly papers and screens involve no active substance and suit any household when placed sensibly. Site electric killers out of reach and away from food preparation areas. For sprays, follow the label: keep children and pets out during application and until surfaces are dry and the room ventilated, and do not treat food or food-contact surfaces unless the label allows it.

Electric killers and traps start catching as soon as they are running, though it takes a day or two before the difference is obvious. Fast knockdown sprays act on the flies present at the time. Fly papers and sticky traps build up over hours or days depending on how many flies are about.

Numbers indoors almost always mean a breeding source rather than flies wandering in. Look for a bin that is not sealed, a blocked or dry drain, standing water, compost close to the house, or pet waste in the garden. Where the flies are large and slow and there is a noticeable smell, look for a dead bird or rodent in a loft, cavity or under floorboards. Removing the source is what stops it - treating the adults without it means they keep arriving.

Almost certainly cluster flies. They gather in lofts, roof spaces and unheated upstairs rooms to overwinter, then become active whenever the sun warms that side of the building. There is no breeding source indoors to remove, so the fix is sealing the gaps they use around soffits, eaves, tiles, vents and window frames, plus a trap or window sticker for those already inside. They return to the same building year after year, which is why sealing properly once is worth the effort. If you are considering treating the roof void itself, check for bats first - it is illegal to use insecticide where bats may be present, and a loft in that situation is a job for a professional.

Fit fly screens to windows and doors, keep doors shut at dusk when flies are most active, and remove what draws them: uncovered food, open or unwashed bins, standing water, and waste in the garden. Read our guide to stopping flies coming into your house for the full sequence.

Where flies keep returning after you have cleaned up and removed the breeding source; where you can find maggots but not the site producing them; where a cluster fly infestation is in a loft that is unsafe to reach, or where bats may be present; or where it is a food business with hygiene obligations to meet.